Stone Studio

The integration of spatial and non-spatial analysis software aims at providing a combination of the most efficient and powerful tools available in both environments (Brenning, 2008). There are various examples where this has been accomplished using access links between different software packages. JGrass, for example, provides integration of the statistic R package into the scripting environment (Rigon et al., 2008). RSAGA provides access to SAGA GIS geoprocessing functions from within the R statistical data analysis environment (Brenning, 2008). So far, Matlab does not include any spatial modelling capability (Pullar, 2004). As such, TopoToolbox is a recent contribution to the endeavor for combining powerful GIS tools for geomorphical and hydrological application with the vast functionality of Matlab and, thus, addresses primarily users that have already gained experience in working with Matlab.

TopoToolbox’ algorithms are largely based on sparse matrix algebra and image processing techniques. Each function is implemented in Matlab-code (*.m-files) and can be easily modified and adapted to specific needs of the user.

So far, the flow direction algorithms implemented in TopoToolbox are the SFD and MFD algorithms. These algorithms tend to produce too linear and too dispersive flow patterns, respectively ([Tarboton, 1997] and Seibert and McGlynn, 2007)Flow randomization and concentration as implemented in TopoToolbox provide means to control this unrealistic behavior. Yet, other algorithms based on triangular facets have been developed to overcome these weaknesses ([Tarboton, 1997], [Seibert and McGlynn, 2007] and [Pelletier, 2008]). These algorithms can be transferred to the linear algebraic approach outlined here and software that implements these algorithms have been made available on the Mathworks File Exchange (http://www.mathworks.com/matlabcentral/, #15818) by Steve Eddins together with various other functions.

A quick user guide

Follow this link (opens in a new window) for a short and yet incomplete introduction.

Download

Download the latest TopoToolbox Version 1.04 at the Community Surface Dynamics Modeling System (CSDMS) code repository (updated January, 5., 2010). For a version history, please see the readme file

Reference:

Schwanghart, W., Kuhn, N. J. (2010): TopoToolbox: a set of Matlab functions for topographic analysis. Environmental Modelling & Software, in press. [DOI: 10.1016/j.envsoft.2009.12.002]

Brenning, 2008 A. Brenning, Statistical geocomputing combining r and saga: the example of landslide susceptibility analysis with generalized additive models. In: J. Böhner, T. Blaschke and L. Montanarella, Editors, SAGA – Seconds Out, Hamburger Beiträge zur Physischen Geographie und Landschaftsökologie vol. 19, Hamburg University, Hamburg (2008), pp. 23–32.